Connecting DC Power to an EX2300 Switch

The power supply is built-in along the rear panel.

Warning: DC-powered switches are intended for installation only in a restricted-access location.

Before you begin connecting DC power to the switch, ensure that you have connected earth ground to the switch chassis.

Caution: Before you connect power to the switch, a licensed electrician must attach a cable lug to the grounding and power cables. A cable with an incorrectly attached lug can damage the switch (for example, by causing a short circuit). To meet safety and electromagnetic interference (EMI) requirements and to ensure proper operation, you must connect the switch to earth ground before you connect them to power. For installations that require a separate grounding conductor to the chassis, use the protective earthing terminal on the switch chassis to connect to the earth ground. For instructions on connecting earth ground, see Connecting Earth Ground to an EX Series Switch.

Note: Grounding is required for DC systems and recommended for AC systems.

Ensure that you have taken the necessary precautions to prevent electrostatic discharge (ESD) damage (see Prevention of Electrostatic Discharge Damage).

• DC power source cables (14 AWG) with ring lug (Molex 0190700067 or equivalent) (not provided) attached to them by a licensed electrician
• Phillips (+) screwdriver, number 2

1. Ensure that the input circuit breaker is open so that the cable leads do not become active while you are connecting DC power.

   Note: The DC power supply in the switch has four terminals labeled INPUT 1+, INPUT 1–, INPUT 2+, and INPUT 2– for connecting DC power source cables labeled positive (+) and negative (–). The terminals are covered by a clear plastic cover.

   Note: The INPUT 1+ and INPUT 2+ terminals are referred to as +RTN and INPUT 1– and INPUT 2– terminals are referred to as –48 V in DC Power Wiring Sequence Warning and DC Power Electrical Safety Guidelines for Switches.

2. Grasp the plastic cover in the middle, gently bend it outward, and pull it out. Save the cover.
3. Remove the screws on the terminals by using the screwdriver. Save the screws.

   Warning: Ensure that the power cables do not block access to switch components or drape where people can trip on them.

4. Connect the power supply to the power sources. Secure power source cables to the power supply by screwing the ring lugs attached to the cables to the appropriate terminals by using the screw from the terminals (see Figure 24).

   Figure 24: Securing the Ring Lugs On the Power Cables to the Terminals on the DC Power Supply

   
   • To connect the power supply to one power source:
     1. Secure the ring lug of the positive (+) DC power source cable to the INPUT 1+ or INPUT 2+ terminal on the DC power supply.
     2. Secure the ring lug of the negative (–) DC power source cable to the INPUT 1– or INPUT 2– terminal on the DC power supply.
     3. Tighten the screws on the power supply terminals until snug by using the screwdriver. Do not overtighten—apply between 8 lb-in. (0.9 Nm) and 9 lb-in. (1.02 Nm) of torque to the screws.
   • To connect the power supply to two power sources:
     1. Secure the ring lug of the positive (+) DC power source cable from the first DC power source to the INPUT 1+ terminal on the power supply.
     2. Secure the ring lug of the negative (–) DC power source cable from the first DC power source to the INPUT 1– terminal on the power supply.
     3. Secure the ring lug of the positive (+) DC power source cable from the second DC power source to the INPUT 2+ terminal on the power supply.
     4. Secure the ring lug of the negative (–) DC power source cable from the second DC power source to the INPUT 2– terminal on the power supply.
     5. Tighten the screws on the power supply terminals on both the power supplies until snug by using the screwdriver. Do not overtighten—apply between 8 lb-in. (0.9 Nm) and 9  lb-in. (1.02 Nm) of torque to the screws.
5. Hook the plastic cover on one side of the terminal block and gently bend it inward to hook it on the other side also.
6. Close the input circuit breaker.

Related Documentation

• Connecting and Configuring an EX Series Switch (CLI Procedure)
• Power Supply in EX2300 Switches